You apply the ConcurrencyCheckAttribute attribute to a property to specify that the property serves as an indicator of whether the data record in the Silverlight application is still current with the data record in the data source. The value of the property should be compared to the value of the property in the data source before updating the data record. If the values are not equal, the data record in the data source has been changed by another process and the update should not overwrite the changed values.